Binding apparatus

ABSTRACT

A binding apparatus for binding a wire around one or more objects is provided. The binding apparatus is adapted to bind the wire such that a predetermined tension in the wire is achieved. A method of binding a wire around one or more objects so as to achieve a desired tension of the wire in the binding is also provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a 371 of International Application No.PCT/EP2010/057331, filed May 27, 2010, for which priority is claimedunder 35 U.S.C. §120; and this application claims priority ofApplication No. 09161234.1 filed in Europe on May 27, 2009, andApplication No. 10151193.9 filed in Europe on Jan. 20, 2010 under 35U.S.C. §119; and this application claims priority of U.S. ProvisionalApplication No. 61/181,431 filed on May 27, 2009, and U.S. ProvisionalApplication No. 61/296,742 filed on Jan. 20, 2010 under 35 U.S.C.§119(e), the entire contents of all of which are hereby incorporated byreference.

FIELD OF THE INVENTION

The present invention relates to a binding apparatus for binding a wirearound one or more objects. In particular the present invention relatesto a binding apparatus wherein a wire is automatically guided around theobject(s).

BACKGROUND OF THE INVENTION

Binding reinforcement bars in concrete constructions is known to be acostly operation. By manual processes a wire is curled around thereinforcing bars, and by means of a wire cutter, the free ends of thewire are twisted such that the reinforcing bars are tied together.

Resent considerations not only related to the costs of binding the barsbut also related to the working environment, has lead to the developmentof hand-held, portable devices for binding.

EP 0751270 shows a device for binding reinforcement bars for concreteconstructions. The device operates by twisting a wire in a loop by aguide arm. A hook thereby binds the reinforcement bars together bytwisting the wire loop.

U.S. Pat. No. 4,252,157 shows a device for binding reinforcement bars,comprising a differential gear for transferring torque from a motor to abinding head and a cutting device, respectively.

EP 1 484 249 discloses a reinforcing bar machine comprising threemotors: a feeding motor, a twisting motor and a sliding motor. Thefeeding motor forms part of a feeding mechanism and is used to feed thewire. A binding wire twisting mechanism includes the twisting motor andthe sliding motor.

Further examples of known binding apparatuses are disclosed in U.S. Pat.No. 5,657,799, EP 0 731 238, EP 0 810 153, EP 0 332 532, EP 0 829 596,U.S. Pat. No. 4,362,192, EP 0 751 270, U.S. Pat. No. 4,252,157, and WO0194206.

It has been found that the ability of the binding apparatus to providethe desired tension in the bound wire is critical for the quality of thebinding. If the wire is tensioned too much, the wire may rupture,whereby the user must repeat the binding action hoping that the secondbinding does also not rupture. If on the other hand the binding is tooloose, the binding will most likely not serve its purpose which in manycases is to ensure that two reinforcing bars are forced into contactwith each other.

With regard to the twisting of the wire by the binding apparatus,binding apparatuses normally are based on one of two principles. A firstin which the wire is twisted as many times as possible e.g. until wireis pulled out of the binding apparatus or until a predetermined torqueis reached during the binding process. In a second principle the wire istwisted a predetermined number of times.

One advantage of twisting the wire a predetermined number of times isthat the binding time for each binding is held at a minimum. The reasonfor this is that in the “as many times as possible” process, anexcessive amount of wire is often provided in order to ensure that thewire ends are twisted a sufficient number of times so as to ensure adesired strength of the binding. The effect is that the ends must betwisted a large number of times which is time consuming.

However, when the wire is twisted a predetermined number of times, it isdifficult to achieve the same tightness of the binding, as the wire patharound the reinforcing bare varies from binding position to bindingposition. In a grid of vertical and horizontal bars, the bars most oftenwill not define a right angle in each intersection—even when this isintended. These small angular variations between intersecting bars makeit difficult to provide the same tension in the wire in each binding.The result is that the bindings are either too loose or breaks becausethey are too tight. Another reason for loose or breaking bindings isthat reinforcing bars on their outer surface often are provided withrips/protrusions for mechanically binding the reinforcing bars to theconcrete. The ribs/protrusions are spaced apart along the outer surfaceof the reinforcing bars and depending on the position of the bindingrelative to the adjacent ribs/protrusions, the wire path may be longeror shorter.

Accordingly, it is an object of an embodiment of the present inventionto provide an apparatus that twists the wire a predetermined number oftimes while it at the same time provides the desired tension in thebindings irrespective of the number of objects to be bound and/or theirthickness and/or the number of ribs and/or the position of the ribsrelative to the binding.

Moreover, it is an object of an embodiment of the present invention toprovide a binding apparatus which reduces the risk of rupture of thewire during binding.

Furthermore, it is an object of an embodiment of the present inventionto provide a binding apparatus with which the risk of loose bindings isreduced or even eliminated.

BRIEF DESCRIPTION OF THE INVENTION

In a FIRST aspect, the present invention relates to a binding apparatusfor binding a wire around one or more objects, the binding apparatusdefining:

-   -   a wire path for guiding a wire around the objects;    -   a wire supply for advancing the wire into the wire path; and    -   a binding tool adapted to retain two ends of the wire relative        to the binding tool and to rotate the ends relative to the wire        path whereby the ends of the wire are twisted around each other,        thus causing the wire to bind the objects together,

wherein

-   -   the binding apparatus is adapted to bind the wire such that a        predetermined tension in the wire is achieved.

One advantage of ensuring a predetermined tension in the wire is thatthe binding is tight enough while at the same time the wire does notbreak during the binding process.

In one embodiment, the binding apparatus further comprising one or morespace defining elements adapted to space the objects apart from thebinding tool. Moreover, the space defining elements may be adapted tovary the distance from the objects to the binding tool in response to atleast one of:

-   -   the torque transferred from the binding tool to the wire during        binding,    -   the axial pressure on the space defining element, and    -   the axial tension in wire during binding.

When the space defining element(s) is/are adapted to vary the distancefrom the objects to the binding tool in response to the torquetransferred from the binding tool to the wire during binding, thendistance may start to be varied when the torque reaches a level of 0.1Nm, such as 0.2 Nm, such as 0.3 Nm, such as 0.4 Nm, such as 0.5 Nm, suchas 1 Nm.

Additionally, when the space defining element(s) is/are adapted to varythe distance from the objects to the binding tool in response to theaxial pressure on the space defining element, then the distance maystart to be varied when the axial pressure on the space defining elementis above 100 Newton, such as 200 Newton, such as 300 Newton, such as 400Newton, such as 500 Newton, such as 600 Newton, such as 700 Newton.

Additionally, when the space defining element(s) is/are adapted to varythe distance from the objects to the binding tool in response to theaxial tension in wire during binding, then the distance may start to bevaried when the axial tension in wire—during binding—100 Newton, such as200 Newton, such as 250 Newton, such as 300 Newton, such as 400 Newton,such as 500 Newton, such is above 600 Newton.

In one embodiment, the apparatus is adapted to twist the ends aroundeach other a predetermined number of times, such as one time, such astwo times, such as three times, such as four times, such as five timesor any number of times there above. In the present, context the wire istwisted one time if the two wire ends are rotated 360 degrees relativeto and around each other. It will be appreciated that in someembodiments, the wire ends may be twisted any multiplum of 360 degreesdifferent from 360 degrees times an integer. As an example the wire endsmay be twisted 1.5 times 360 degrees i.e. 540 degrees.

The width of the reinforcing bars and the position of the wire relativeto the protrusions on the outer surface of the reinforcing barsdetermine how much wire remains to be twistable once the wire has beenguided around the reinforcing bars. If the reinforcing bars arewide/thick, a shorter piece of wire remains to be twistable.Accordingly, the provision of a space defining element which is adaptedto vary the distance from the objects during the binding process allowsfor a larger part to the wire to be accessible for twisting. Inparticular this feature allows for the wire to be twisted thepredetermined number of times, e.g. two times, independent on the widthof the reinforcing bars and/or the position of the protrusions on theouter surface of the reinforcing bars relative to the wire.

In one embodiment, one space defining element is provided.Alternatively, two or more space defining elements may be provided suchas two, three, four, five or six space defining elements.

The space defining element(s) may be movable from a distal position andtowards a proximal position or even into said proximal position. Thedistance travelled by the space defining elements when moved from thedistal to the proximal position may be in between 5 mm and 50 mm, suchas 50 mm, such as 15 mm such as 20 mm such as 30 mm such as 40 mm. Thepath along which each of the space defining elements travel duringmovement between its distal and its proximal position may be linear orcurved. The latter case may be achieved by arranging the space definingelements pivotally.

In one embodiment, a distal protrusion is may be provided for preventingthe space defining element from being biased past the distal position.Similarly, proximal protrusion may be provided for preventing the spacedefining element from being moved past its proximal position.Accordingly, the space defining element is movable between the distaland the proximal protrusions.

In one embodiment, the space defining element is movable from a distalposition relative to the binding tool and towards a binding tool,moreover the space defining element may be biased towards the distalposition. The space defining element may be biased towards the distalposition by means of at least one of: a resilient element, a pneumaticarrangement and a hydraulic arrangement, an electrical motor, or anyother biasing means. The resilient element may be a tension element or acompression element or a torsional element, such as a tension orcompression or torsional spring. In one embodiment, the resilientelement is an elastic member made out of rubber—synthetic or natural. Inone embodiment, the resilient element is a cantilever spring or ahelical spring. The pneumatic arrangement may comprise one or morepneumatic cylinders. Similarly, the hydraulic arrangement may compriseone or more hydraulic cylinders.

The biasing means may have a spring constant which determines the forcewith which the space defining element is biased towards the distalposition. In one embodiment, the spring constant is in the range 5-50N/mm, such as 10 N/mm, such as 12 N/mm, such as 14 N/mm, such as 16N/mm, such as 18 N/mm, such as 20 N/mm, such as 25 N/mm, such as 30N/mm, such as 35 N/mm, such as 40 N/mm, such as 45 N/mm.

In one embodiment, the spring constant is chosen such that if thebinding apparatus is positioned on top of the reinforcing bars in aposition in which the apparatus is allowed to rest on the reinforcingbars, then the weight of the binding apparatus will cause aninsignificant movement of the space defining element away from itsdistal position. An insignificant movement will in one embodiment meanthat the space defining element remains in physical contact the distalprotrusion. In another embodiment, the insignificant movement shall beconstrued such that space defining element has moved less than 1 percentof the distance between its distal and proximal position.

In some embodiment, it may be desirable to be able to vary the distalposition. This is especially the case if the reinforcing bars to bebound changes from begin very wide to being very thin and vice versa.

Accordingly, the distal position of the space defining element may beadjustable by means of an adjusting arrangement. In one embodiment, theadjusting arrangement comprises an adjustment plate adapted to adjustthe distance from the binding head to the distal position of the spacedefining element. The adjustment plate may be adapted to be interposedbetween the space defining element(s) and the binding apparatus. In oneembodiment, binding apparatus comprises a plurality of interchangeableadjustment plates, each of which is adapted to provide different distalpositions of the space defining element.

The thickness of the adjustment plates may be 1 mm, such as 2 mm, suchas 3 mm, such as 4 mm, such as 5 mm, such as 6 mm, such as 7 mm, such as8 mm, such as 8 mm, such as 10 mm, such as 11 mm, such as 12 mm, such as13 mm, such as 14 mm, such as 15 mm, such as 16 mm, such as 17 mm, suchas 18 mm, such as 19 mm, such as 20 mm, such as 22 mm, such as 24 mm,such as 26 mm, such as 28 mm, such as 30 mm, such as 32 mm, such as 34mm, such as 36 mm, such as 38 mm, such as 40 mm, such as 42 mm, such as44 mm, such as 46 mm, such as 48 mm, such as 50.

It will be appreciated that the thicker the adjustment plate is, thefurther the reinforcing bars are spaced apart form the binding tool, andthus the longer is the ends which are used to bind the wire.Additionally it will be appreciated that the thinner the adjustmentplate is, the closer the reinforcing bars are to the binding tool andthe shorter is thus the wire ends.

During use, the user can choose the adjustment plate which yields thedesired tension in the wire during binding. It will be appreciated thatthe thicker the reinforcing bars are, the longer must be the pieces ofwire which are twisted during binding in order to achieve the desirednumber to twists during binding. Additionally, it will be appreciatedthat the thinner the reinforcing bars are, the shorter need the wireends be in order to be able to achieve the desired number of twists ofthe wire ends.

In an alternative embodiment, the distal position may be adjustable bymeans of a handle which is coupled to a mechanism such that when thehandle is turned, the distal position is changed. In one embodiment, thehandle takes the form of a ring shaped element accessible from the outersurface of the device. The mechanism may comprise a threaded memberwhich is rotatable by means of the handle and which when rotated causesthe distal position to be changed.

In an alternative embodiment, the adjustment arrangement comprises atleast one of a hydraulic means for adjusting the distal position, apneumatic means for adjusting the distal position and an electricalmeans for adjusting the distal position. The hydraulic means may be ahydraulic cylinder. The pneumatic means may be a pneumatic cylinder. Theelectrical means may be a linear actuator. It will be appreciated thatwhen pneumatic means may used to adjust the distal position, the entirebinding apparatus may be fluidly coupled to a pneumatic source. In thelatter embodiment, any motor of the binding apparatus may be a pneumaticmotor.

The binding apparatus may be adapted to slacken the wire prior totwisting depending on the width of the reinforcing bars. Accordingly, inone embodiment, the binding apparatus comprises a retainer for retaininga front end of the wire, and the wire supply is adapted to:

-   -   advance the front end of the wire into the wire path such that        the wire is guided around the objects and the front end is        received in the binding tool and is retained therein by the        retainer;    -   tighten the wire; and    -   slacken the wire depending on the length of the tightened wire        and/or the size of the objects such that:        -   the degree of slackening of the wire is the lowest, if the            wire has a first length and/or the objects have a first            size,        -   the degree of slackening of the wire is the highest, if the            wire has a second length and/or the objects have a second            size, and        -   the degree of slackening of the wire is between said lowest            and highest slackening, if the wire has a third length            and/or the objects have a third size,

wherein the first length is shorter than the second length which isshorter than the third length, and

wherein the first size is smaller than the second size which is shorterthan the third size.

By providing an apparatus which adjusts the tension in the wire inaccordance with the length of the wire to be bound and/or the size ofthe objects to be secured together, the correct tension may be achieved.Thus the resulting binding will not be too loose or too tight.

The inventors have surprisingly found that in order to achieve thedesired tension, the needed degree of slacking/loosening of the wire isnot linearly dependent on the length of the wire or the size of theobjects to be bound. In fact, the inventors have found that mediumlength wires must be slackened more than both short and long wires.

In the content of the present invention the term “tighten” shall beunderstood such that the length of the wire which encirculates theobjects to be bound is made shorter i.e. the binding apparatus pulls inone of the ends of the wire. Contrary hereto the term “slacken” shall—inthe context of the present invention—be understood such that the lengthof the wire which encirculates (is guides around) the objects to bebound is made longer as the binding apparatus feeds/advances more wire“into” the encirculating part of the wire.

In one embodiment, the degree of slackening is measured in percent ofthe length of the wire which encirculates the objects to be bound. Inanother embodiment, the degree of slackening of the wire is measured inmillimeters.

Accordingly in one embodiment, the ‘slackening the wire’ shall beunderstood in the following manner:

-   -   slacken the wire depending on the length of the tightened wire        and/or the size of the objects such that:        -   the wire is slackened a length or percentage A, if the wire            has a first length and/or the objects have a first size,        -   the wire is slackened a length or percentage B, if the wire            has a second length and/or the objects have a second size,            and        -   the wire is slackened a length or percentage C, if the wire            has a third length and/or the objects have a third size,

wherein A<C<B, and

wherein the first length is shorter than the second length which isshorter than the third length, and

wherein the first size is smaller than the second size which is shorterthan the third size.

Alternatively, or as a supplement, the wire supply may be adapted to

-   -   advance the front end of the wire into the wire path such that        the wire is guided around the objects and the front end is        received in the binding tool and is retained therein by the        retainer;    -   tighten the wire;    -   determine the length of the wire which is guided around the        objects to be bound, and    -   slacken the wire in response the length of the wire which is        guided around the objects to be bound.

Alternatively, or as a supplement, the wire supply may be adapted toslacken the wire depending on the length of the tightened wire and/orthe size of the objects such that:

-   -   the degree of the slackening of the wire is in a lower range, if        the wire has a length which is below a first length-threshold        and/or the objects have a size which is below a first        size-threshold,    -   the degree of slackening of the wire is in a middle range, if        the wire has a length which is above a third length-threshold        and/or the objects have a size which is above a third        size-threshold, and    -   the degree of slackening of the wire in an upper range, if the        wire has a length which is between the first and third        length-threshold and/or the objects have a size which is between        the first and third size-threshold,

wherein the first length-threshold is below the third length-thresholdand the first size-threshold is below the third size-threshold, andwherein the wire is slackened less in the lower range than in the middlerange and more in the upper range than in the middle range.

Examples of the first length-threshold are five centimeters, sixcentimeters, seven centimeter, eight centimeters, nine centimeters, tencentimeters, eleven centimeters, twelve centimeters, thirteencentimeters or any other value.

Examples of the third length-threshold are ten centimeters, elevencentimeters, twelve centimeter, thirteen centimeters, fourteencentimeters, fifteen centimeters, sixteen centimeters, seventeencentimeters, eighteen centimeters or any other value.

In one embodiment, the degree of slackening of the wire is in the middlerange, if the wire has a length which is between the first and a secondlength-threshold and/or the objects have a size which is between thefirst and a second size-threshold and wherein:

-   -   the first length-threshold is below the second length-threshold,        and the second length-threshold is below the third        length-threshold, and    -   the first size-threshold is below the second size-threshold, and        the second size-threshold is below the third size-threshold.

In the latter embodiment, the degree of slackening is in the lower rangewhen the wire is below the first length-threshold, in the middle rangewhen the wire in between the first and the second length-threshold, inthe upper range when the wire in between the second and the thirdlength-threshold and in the middle range when the wire is above thethird length threshold.

Alternatively, or as a supplement, the degree of slackening may be inthe lower range when the objects have a size below the firstsize-threshold, in the middle range when the objects have a size betweenthe first and second size-threshold, in the upper range when the objectshave a size between the second and third size-threshold and in themiddle range when the objects are above the third size-threshold.

In the context of the present invention the size of the objects to bebound may be the diameter of the smallest circle encircling the objects.Alternatively, the size may be the longest dimension of the objects in across-section to the objects. Alternatively, the size may be the area orcircumference of the aforementioned circle.

In one embodiment, the degree of slackening is defined by a tablecomprising empiric data. Such a table may in one embodiment comprise twocolumns. A first containing rows each with a different length of thewire in the tightened state, and a second column containingcorresponding degrees of slackening of the wire for the respectivelength of wire. The degree of slackening may be in percent or inmillimeters. Thus in each row is specified a length of the tightenedwire (the first column in the row) and the corresponding degree ofslackening (the second column in the row).

Alternatively, or as a supplement, the wire supply may be adapted toslacken the wire on the basis of a polynomial in which at least oneindeterminate is the length of the tightened wire or the size of theobjects. This could be a polynomial of a fourth degree e.g. on theformula ax⁴+bx³+cx²+dx+e, where x is the size of the objects or thelength of the wire and a, b, c, d, and e are constants. Alternatively,the polynomial is a fifth degree, a sixth degree, seventh degree etc.polynomial.

In one embodiments where the apparatus comprises the aforementionedadaptive space defining elements (which are adapted to vary the distancefrom the objects), the slackening function may be linear i.e. such thewider the objects to be bound are the more the wire is slackened afterhaving been tightened.

In one embodiment, the function used to slacken the wire may be aone-to-one function. In the present context a “one-to-one function”shall be understood as a function defining a relation of x,y where forevery x there is one and only one value of y assigned, and at the sametime for every y there is one and only one value x. One example of sucha function is a linear function e.g. y=ax+b.

In one embodiment, the binding tool comprises:

-   -   a binding head, and    -   an inner tool member slidingly received in the binding head such        that the inner tool member and the binding head are locked for        relative rotation, the inner tool member being connected to a        rotatable spindle such that rotation of the spindle causes the        inner tool member to move, axially relative to the binding head,        in the direction of a locking position in which the inner tool        member is locked for axial movement relative to the binding        head, whereby further rotation of the spindle causes concurrent        rotation of the inner tool member and the binding head in a        first direction relative to the wire path.

In one embodiment, the binding apparatus comprises a means fordetermining the tension of the wire. This could be a means fordetermining the torque during applied to the wire during the bindingprocess. Once the torque has reached a predetermined value, the bindingprocess may be halted as the desired tension in the wire is achieved.

In one embodiment, the binding apparatus defines a wire path for guidinga wire around one or more objects. In this embodiment the bindingapparatus comprises:

-   -   a wire supply for advancing the wire into the wire path; and    -   a binding tool forming a passage for the wire into and out of        the wire path and being rotatable relative to the wire path, and        comprising:        -   a binding head, and        -   an inner tool member slidingly received in the binding head            such that the inner tool member and the binding head are            locked for relative rotation, the inner tool member being            connected to a rotatable spindle such that rotation of the            spindle causes the inner tool member to move, axially            relative to the binding head, in the direction of a locking            position in which the inner tool member is locked for axial            movement relative to the binding head, whereby further            rotation of the spindle causes concurrent rotation of the            inner tool member and the binding head in a first direction            relative to the wire path.

The concurrent movement of the inner tool member and the binding head inthe first direction relative to the wire path, causes the free ends of awire piece, which have been guided around the objects by the bindingapparatus, to be twisted relative to each other, whereby the wire pieceis bound around the object(s). Prior to and/or during said bindingprocess, the wire may be tightened/tensioned such that a tight bindingmay be provided, i.e. a binding wherein the objects are forced towardseach other due to the tensioned wire piece.

At least a part of the binding apparatus may comprise a plastic materialsuch as a reinforced plastic material, metal material such as an acidproof material, a fibre glass material, or any other material suitableto be used in a concreting environment.

The binding apparatus may be used to bind any two (or more) objectstogether, such as reinforcing bars, tree branches, plastic tubes e.g.heating tubes for floor heating systems, wires etc. As an example, thebinding apparatus may be used to secure an element to a largerstructure, such as fastening an electrical wire to a structure in orderto secure the wire in a predetermined position. It will be appreciatedthat the binding apparatus may also be used to bind a wire to a singleobject, e.g. so as to provide a coat-hook or a handle or so as to mark aposition on the object.

The wire may be any wire suitable for binding, such as a metal wire e.g.coated with a non-metal material, or a plastic wire or any other wiresuitable to be used in the binding apparatus. In one embodiment, thewire may be any wire which is sufficiently rigid to be reshaped/bent tohave a predetermined curvature and to maintain said curvature for aperiod of time of at least 30 seconds, such as 1 minute, such as 2minutes, such as 5 minutes.

In use, the wire may be provided on a roll which may be inserted intothe wire supply, such that the wire may be feed into the binding headduring binding of the wire. The wire supply may comprise a motor coupledto feeding rollers for feeding/advancing the wire into the binding head.In one embodiment, the apparatus comprises one set of rollers (each setcomprising two opposing rollers between which the wire is provided). Inanother embodiment, the apparatus comprises plurality of sets of rollerssuch as two, such as three, such as four, such as five.

The wire supply may comprise one or more sensors such as photo-sensorsor mechanical-sensors, for detecting the position of the wire. As anexample, a sensor may be provided upstream (relative the feedingdirection of the wire) of the feeding rollers such that upon manualinsertion of a wire into the wire supply, the rollers may be activatedupon detection of a wire by the upstream sensor. When the manuallyinserted wire meets the rotating rollers, the rollers continue theadvancement of the wire until the supplied wire ends.

Moreover, a sensor may be provided downstream the feeding rollers, andthe distance between the upstream and the downstream sensors maycorrespond to the minimum length a wire must have in order to be guidedaround and bound to one or more objects. Thus, upon user activation ofthe apparatus, the apparatus may be adapted to determine whether thewire is sufficiently long to perform a binding action, and may preventthe process in case the wire is not sufficiently long.

Either or both of the upstream and downstream sensors may be magneticsensors arranged to detect the presence of the wire. It will beappreciated, that in order for magnetic sensor to be able to detect thewire, the wire must comprise a magnetic material such a ferromagneticmaterial. As mentioned above the sensor(s) may be any kind of sensor(s)such as photo-sensors, mechanical-sensors.

Alternatively, or as a supplement, the binding apparatus may comprise arevolution counter adapted to count the number of revolutions made bythe feeding rollers. As one revolution of the feeding rollerscorresponds to a predetermined length of wire, the revolution countermay be adapted to output a signal corresponding to a wire length. As therollers are in direct contact with the wire, determination of the numberof revolutions will provide a direct measure of the length of the wirewhich is advanced.

In one embodiment the apparatus comprises a revolution counter and theaforementioned upstream sensors. In the latter embodiment, the apparatusmay be adapted to be operated as follows: If during feeding of wire, theupstream sensor is no longer able to detect the wire i.e. the wiresupply is empty, the apparatus may, by means of the revolution counter,be adapted to determine the length of the wire which, in connection withthe current binding action, has already been feed by means of therollers. If said length is below a predetermined length e.g. the lengthneeded to perform a binding action, the binding apparatus may be adaptedto retract the feed wire and signal to the user, that the wire is notlong enough for binding and that a new wire should be inserted into thewire supply.

In one embodiment, the binding apparatus comprises the revolutioncounter and is adapted to determine the total length of wire alreadyused and the length of the wire remaining in the wire supply. Moreover,the binding apparatus may be adapted to calculate the number of bindingswhich may be performed by means of the wire remaining in the wiresupply. Additionally, the binding apparatus may be adapted to determinean average time elapsing between each binding, and, thus, the time leftuntil the wire must be changed. The latter information may be used bythe user to determine whether the remaining wire is long enough tocontinue until the next break or until the end of the working day.

In one embodiment, the apparatus is adapted to determine/calculate theamount of wire which is needed, and on the basis thereof operate thewire supply such that once the wire has been tightened, the wire isslackened so as to achieve the desired tightness of the wire. It will beappreciated that the tighter the binding is, the more prone thewire/binding will be to breaking/rupturing. Additionally it will beappreciated that the looser the binding is, the higher is the risk thatthe elements to be bound may move relative to each other in the area ofthe binding.

In one embodiment the apparatus comprises a processor for controllingone or more of the motors and the sensors. The processor may comprise amemory for storing information. In one embodiment, the processor isadapted to control the motor for feeding the wire, such that the wire isloosened to the desired extend prior to the tying process.

Moreover, a table may be stored in the memory, which table comprisesinformation as to the degree of loosening depending on the length of thewire. The information stored in the table may be stored into the memoryprior to the sale of the product e.g. during manufacture. Alternatively,or as a supplement, the user may store the information into the memoryduring use of the device such that the wire is tightened at a leveldesired by the user.

In one embodiment, the information is determined by the manufacturer asa result of empiric tests. In yet another embodiment, the processor isadapted to loosen the wire based on a formula such as a formula whichapproximately provides the same result as the values determinedempirically.

The wire supply may be adapted to advance the wire into the wire path,which is the path along which the wire is guided from the binding tool,around the object(s) and back to the binding tool. Said path may bedefined by one or more of: a first passage of the binding head, a secondpassage of the binding head, a first guiding jaw and a second guidingjaw, as is described in further detail below.

The inner tool member is slidingly received in the binding head and maybe moved between an initial position and a locking position. When theinner tool member is positioned in the initial position, it may be movedin a first direction, relative to the binding head, whereby it is movedtowards the locking position. When inner tool member is positioned inthe locking position it is locked for further movement in the firstdirection, relative to the binding head, but may be moved in theopposite direction, i.e. in the direction of the initial position.

In order to achieve that rotation of spindle causes the inner toolmember to move translationally, the inner tool member may be threadedlyconnected to the spindle, e.g. by means of a single thread or a multiplethread comprising two, three, four five, six, seven or eight threads. Inone embodiment, an inner surface of the inner tool member is threadedand arranged to engage a threaded outer surface of the spindle.Alternatively, an inner surface of the spindle may be threaded andarranged to engage a corresponding threaded outer surface of the innertool member. At least one of the threads may be an ISO-metric thread, asquare thread, or a trapezium thread or any other thread suitable totransform the rotation of the spindle to a translational movement of theinner tool member. In one embodiment, the inner tool member is connectedto the spindle by means of a ball screw assembly and/or a roller screw.

The binding apparatus may comprise a motor for rotating the spindle. Themotor may be an electrical motor and the binding apparatus may comprisea power supply such as a battery, for providing power to the electricalmotor. Alternatively, the binding apparatus may comprise a cable forconnecting the apparatus to mains or an external battery. The motor maybe connected directly to the spindle or via one or more gears.

When the spindle is rotated at least a part of the torque is transferredto the inner tool member, which, thus, must be locked for rotation inorder to achieve the translational movement. Accordingly in oneembodiment, the binding head, relative to which the inner tool member islocked for rotation, may be partly locked for rotation in a firstdirection. By partly locked for rotation is meant that the binding headis prevented from rotating in the first direction unless a torqueapplied to the binding head is above a predetermined threshold. In oneembodiment, an adjustable spring determines the predetermined threshold.The spring may be adjustable by the user.

Moreover, the binding head may be locked for rotation in a directionopposite the first direction, relative to the wire path, wherebyrotation of the spindle in the opposite direction causes the inner toolmember to be moved away from the locking position and towards theinitial position.

The binding tool may define a first passage defining an inlet and anoutlet, and a second passage defining an outlet. In one embodiment, thewire supply is adapted to advance the wire through the first passage byadvancing the wire into the inlet and out of the outlet, and back intothe inlet of the second passage so as to guide the wire around theobject(s). During movement between the outlet of the first passage andthe inlet of the second passage, the wire may follow the wire path.

The binding apparatus may comprise a cutting tool which is arranged tocut the wire during movement of the inner tool member towards thelocking position. In one embodiment, the tool member is adapted to cutthe wire inside the first passage or in an area of the inlet of thefirst passage. The cutting tool may comprise a first cutting edge whichduring cutting is moved towards either a second cutting edge or acontact surface, through a substantially non-rotational movement, suchas a substantially pure translational movement in the direction of thelocking position. The first cutting edge and one of the second cuttingedge and the contact surface may be adapted to be moved directly towardseach other or may be arranged to slide past each other like the cuttingedges of a scissor. When the a wire is inserted through the firstpassage and received in the second passage, cutting of the wire causes apiece of wire to be separated from the wire of the wire supply. Saidwire piece comprises a cut end and a feed/fed end. Subsequently to thecutting action, the cut end may be positioned in the first passage or inthe area of the inlet of the first passage, and the feed/fed end may bepositioned in the second passage. In an embodiment, the first cuttingedge is defined by the inner tool member. In a further embodiment, thesecond cutting edge or the contact surface may be defined by a guidingmember for guiding the wire into the first passage.

In order to ensure that the wire which has passed through the firstpassage is received in the second passage, at least a part of the wirepart may be defined by one or more guiding jaws. In one embodiment, thebinding apparatus comprises at least one of a first and a second guidingjaw. The first and second guiding jaws may be spaced apart such that anobject to be bound may be inserted into a cavity defined by the firstand second guiding jaw, e.g. by moving the binding apparatus in over theobject(s). Due to the gap between the first and second guiding jaw, thefirst guiding jaw may be adapted to guide a wire from the first guidingjaw to the second guiding jaw. During use, the feed/fed end of the wireis feed from the outlet of the first passage on to a first guidingsurface of the first guiding jaw, upon further feeding of the wire thefeed/fed end slides along the first guiding surface and leaves the firstguiding jaw whereby the feed/fed end is advanced in free air. However,due to the shape of the first guiding jaw/surface, the feed/fed end ofwire is guided in the direction of the second guiding jaw and finallyreceived in by the second guiding jaw. Subsequently, the second guidingjaw guides the feed/fed end into the inlet of the second passage.

In one embodiment, at least one of the first and second guiding jaw isadapted to be rotated between a first and a second position such thatwhen positioned in the first position, an object to be tied is encircledby the binding apparatus and such that when positioned in the secondposition an object to be tied may be advanced into a binding position bybeing moved through a passage defined between end surfaces the first andsecond guiding jaws. Each of the rotatable guiding jaws may be biasedtowards the first position and may comprise means for forcing it intothe second position. Such means may be an inclined surface provided atthe end surfaces of the first and/or the second guiding jaw.

Moreover, the first and/or second guiding jaws may be releasablereattachable to the binding apparatus, so as to allow a user to replacejaws.

The first and second passage may be arranged with respect to each other,such that a wire feed out of the first passage must be reshaped, such asbend, in order to be received in the second passage. Accordingly, atleast a part of the wire path may be defined by a shaping tool adaptedto shape the wire when advanced through the shaping tool, so as to allowthe wire to be received in the second passage of the binding tool. Theshaping tool may be defined by one or more of the binding tool and thefirst guiding jaw. In order to reshape/bend the wire, the shaping toolmay comprises at least three shape-defining surfaces which are arrangedwith respect to each other, such that the wire is formed so as to havewith a predetermined curvature, when the feed/fed end of the wire ismoved translationally into the shaping tool. In one embodiment, at leastone shape-defining surface is movable in relation to at least one othershape-defining surface, so as to change the curvature of a wire feedthrough the shaping tool. At least one of the inner tool member, thebinding head and the first guiding jaw, may define at least one guidingsurface adapted to guide the wire from the wire supply and into theshaping tool.

In order to allow the wire to be tightened around the object(s) theshaping tool may be shaped such that upon tightening of the wire, thewire is brought out of engagement with the shaping tool, whereby thewire may be tightened around at least a part of the one or more objects.In one embodiment, the shaping tool may comprise a pawl mechanismallowing the wire to be brought out of engagement with the shaping tool.In another embodiment tightening of the wire causes the wire to be movedsideward's out of engagement with the shaping tool as is described infurther detail in the description of the figures.

When the feed/fed end has been received in the second passage, thebinding apparatus may be adapted to tighten the wire. Accordingly, toprevent that said tightening of the wire causes the feed/fed end to bepulled out of the second passage, the second passage may comprise aretainer for preventing movement of the feed/fed end in a directionopposite the insertion direction. As the second passage is at leastpartly defined by the binding tool, the retainer, the inner tool memberand/or the binding head comprise(s) the retainer. However subsequent tobinding the wire piece, the feed/fed end should preferable be moved outof engagement with the retainer and, thus, the retainer may be adaptedto allow the feed/fed end to be (re)moved in a direction transverse tothe insertion direction, whereby the feed/fed end is moved out ofengagement with the retainer. In one embodiment the removal directiondefines an angle of 45-90 degrees relative to the insertion direction,such as 60-90, such as 80-90 degrees.

The inner tool member and/or the binding head may be adapted to retainthe cut end of the wire piece, by moving the inner tool member into thelocking position, whereby the cut end is prevented from being retractedfrom the first passage. In one embodiment, the inner tool membercomprise a first retaining surface and the binding head comprises asecond retaining surface, and the cut end is retained in the firstpassage when said cut end is positioned between and in contact with thefirst and second retaining surface, and said surfaces are forced towardseach other.

When the cut end is retained between the first and second retainingsurfaces, further axial movement of the inner tool member relative tothe binding head is prevented, and further rotation of the spindlecauses the inner tool member and the binding head (the binding tool) torotate together as described previously. In one embodiment, the rotationof the binding tool is caused by rotational forces applied from thethread of the spindle to the inner tool member. When the inner toolmember is not positioned in the locking position, such rotational forcescauses the inner tool member to be moved axially due to the thread, butwhen the inner tool member is positioned in the locking position, axialmovement is prevented whereby the binding tool will rotate.Alternatively, or as a supplement, the inner tool member may comprise anabutment surface adapted to engage a corresponding abutment surface ofthe binding head when the inner tool member is positioned in its lockingposition, such that rotation of the inner tool member is transferred tothe binding head via the abutting surfaces.

In some embodiments, the geometry of the first and the second passagecauses the feed/fed end and the cut end to intersect each other wherebyat least a part of the binding tool is encircled and, thus, trapped bythe wire ends. As such wires may be relatively stiff, a user must applyrelatively large forces to remove the binding apparatus. Accordingly inone embodiment, the inner tool member and/or the binding head is/areadapted to reshape at least one the cut end and the feed/fed end uponmovement of the inner tool member away from its locking position, suchthat the wire ends do not intersect each other and/or such that thebinding tool is not trapped by the wire ends. Upon such reshaping, thebinding apparatus may be easily removed by the user.

In one embodiment, the binding apparatus comprises one or more spacersfor ensuring a distance between the binding tool and the objects to betied. The spacers provide the advantage that the tightness of thebinding may be controlled, in embodiments wherein the binding toolduring binding is adapted to be rotated a predetermined number of timesrelative to the wire path, such as one, two, three, four, five, or six.It will be appreciated that the closer the objects are to the bindingtool, the tighter the binding will be and vice versa.

At least one of the spacers may define grooves/indentations adapted toreceive the object to be bound. In one embodiment, the groove is definedin a surface facing the object to be bound during operation. The groovemay extend in a direction transverse to the spacer e.g. such that anobject received in the groove extends through axis of rotation of thespindle and the inner tool member.

In another embodiment the binding apparatus is adapted to tighten thewire as much as possible, and subsequently loosen the wire so as toprovide the desired tightness of the binding.

The invention according to the first aspect may comprise one or more ofthe following embodiments:

Embodiment One

A binding apparatus defining a wire path for guiding a wire around oneor more objects, the binding apparatus comprising: a wire supply foradvancing the wire into the wire path; and a binding tool forming apassage for the wire into and out of the wire path and being rotatablerelative to the wire path, and comprising: a binding head, and an innertool member slidingly received in the binding head such that the innertool member and the binding head are locked for relative rotation, theinner tool member being connected to a rotatable spindle such thatrotation of the spindle causes the inner tool member to move, axiallyrelative to the binding head, in the direction of a locking position inwhich the inner tool member is locked for axial movement relative to thebinding head, whereby further rotation of the spindle causes concurrentrotation of the inner tool member and the binding head in a firstdirection relative to the wire path.

Embodiment Two

A binding apparatus according to embodiment one, wherein the bindinghead is locked for rotation in a direction opposite the first direction.

Embodiment Three

A binding apparatus according to embodiment one or two, wherein the wiresupply is arranged to advance the wire through a first passage and backinto a second passage via the wire path, the first and second passagesbeing defined by the binding tool.

Embodiment Four

A binding apparatus according to any of the preceding embodiments,further comprising a cutting tool which is arranged to cut the wireduring movement of the inner tool member towards the locking position.

Embodiment Five

A binding apparatus according to embodiment four, wherein the cuttingtool comprises a first cutting edge which during cutting is movedtowards one of a second cutting edge and a contact surface, through asubstantially non-rotational movement.

Embodiment Six

A binding apparatus according to embodiment five, wherein the inner toolmember defines the first cutting edge.

Embodiment Seven

A binding apparatus according to any of the preceding embodiments,wherein at least a part of the wire path is defined by one or moreguiding jaws.

Embodiment Eight

A binding apparatus according to embodiment seven, wherein at least apart of the wire path is defined by a shaping tool adapted to shape thewire when advanced through the shaping tool, so as to allow the wire tobe received in the second passage of the binding tool.

Embodiment Nine

A binding apparatus according to embodiment eight, wherein the shapingtool comprises at least three shape-defining surfaces which are arrangedwith respect to each other, such that the wire is formed so as to havewith a predetermined curvature, when the wire is moved translationallyinto the shaping tool.

Embodiment Ten

A binding apparatus according to embodiment eight or nine, wherein theinner tool member and/or the binding head define at least one guidingsurface adapted to guide the wire from the wire supply and into theshaping tool.

Embodiment Eleven

A binding apparatus according to any of embodiments eight to ten,wherein a first guiding jaw of the one or more guiding jaws is arrangedto guide the wire into the shaping tool.

Embodiment Twelve

A binding apparatus according to embodiment eleven, wherein a secondguiding jaw of the at least one guiding jaw is arranged to receive thewire when feed from the first guiding jaw and to guide the wire into thesecond passage.

Embodiment Thirteen

A binding apparatus according to any of embodiments three to twelve,wherein the inner tool member and/or the binding head comprise(s) aretainer adapted to retain a feed/fed end of the wire, upon insertion,in an insertion direction, of said end into the second passage, suchthat movement of the feed/fed end in a direction opposite the insertiondirection is prevented.

Embodiment Fourteen

A binding apparatus according to embodiment thirteen, wherein theretainer is adapted to allow the feed/fed end to be moved in a directiontransverse the insertion direction whereby the feed/fed end is moved outof engagement with the retainer.

Embodiment Fifteen

A binding apparatus according to any of the preceding embodiments,wherein the inner tool member and/or the binding head is/are adapted toretain a cut end of a wire piece which is cut from the wire and whichcomprises the cut end and the feed/fed end, by moving the inner toolmember into the locking position, whereby the cut end is prevented frombeing retracted from the first passage.

Embodiment Sixteen

A binding apparatus according to any of the preceding embodiments,wherein the inner tool member comprises an abutment surface adapted toengage a corresponding abutment surface of the binding head when theinner tool member is positioned in its locking position, such thatrotation of the inner tool member is transferred to the binding head viathe abutting surfaces.

Embodiment Seventeen

A binding apparatus according to embodiment fifteen or sixteen, whereinthe inner tool member and/or the binding head is/are adapted to reshapeat least one the cut end and the feed/fed end upon movement of the innertool member away from its locking position.

Embodiment Eighteen

A binding apparatus according to any of embodiments seven to seventeen,wherein the shaping tool is shaped such that upon tightening of thewire, the wire is brought out of engagement with the shaping tool,whereby the wire may be tightened around at least a part of the one ormore objects.

In the context of the present invention, the terms feed/fed end and cutend may be substituted by the terms first end and second end, as thefirst end need not have been fed into the device and as the second endneed not have been cut by the device. As an example the wire may be aprecut piece of wire of a predetermined length. This piece of wire couldhave been placed around the objects to be bound by the user or byanother device.

The invention according to the first aspect may comprise any combinationof features and elements of the invention according to the second and/orthird and/or fourth and/or fifth aspect of the invention.

In a SECOND aspect the present invention relates to a method of bindinga wire around one or more objects so as to achieve a predeterminedtension of the wire in the binding, the method comprising the steps of:

-   -   placing the wire around the objects such that two pieces of the        wire extend in the same direction,    -   binding the wire such that a predetermined tension in the wire        is achieved.

In one embodiment, the step of binding the wire comprises the step of:

-   -   tightening the wire; and    -   slackening the wire depending on the length of the tightened        wire and/or the size of the objects such that:        -   the degree of slackening of the wire is the lowest, if the            wire has a first length and/or the objects have a first            size,        -   the degree of slackening of the wire is the highest, if the            wire has a second length and/or the objects have a second            size, and        -   the degree of slackening of the wire is between said lowest            and highest slackening, if the wire has a third length            and/or the objects has a third size,    -   wherein the first length is shorter than the second length which        is shorter than the third length, and

wherein the first size is smaller than the second size which is shorterthan the third size.

In one embodiment, the degree of slackening is measured in percent ofthe length of the wire which encirculates the objects to be bound. Inanother embodiment, the degree of slackening of the wire is measured inmillimeters.

Accordingly in one embodiment, the step of slackening the wire comprisesthe step of:

-   -   slacken the wire depending on the length of the tightened wire        and/or the size of the objects such that:        -   the wire is slackened a length or percentage A, if the wire            has a first length and/or the objects have a first size,        -   the wire is slackened a length or percentage B, if the wire            has a second length and/or the objects have a second size,            and        -   the wire is slackened a length or percentage C, if the wire            has a third length and/or the objects have a third size,

wherein A<C<B, and

wherein the first length is shorter than the second length which isshorter than the third length, and

wherein the first size is smaller than the second size which is shorterthan the third size.

In the alternative—or as a supplement the wire may be slackeneddepending on the length of the tightened wire and/or the size of theobjects such that:

-   -   the degree of the slackening of the wire is in a lower range, if        the wire has a length which is below a first length-threshold        and/or the objects have a size which is below a first        size-threshold,    -   the degree of slackening of the wire is in a middle range, if        the wire has a length which is above a third length-threshold        and/or the objects have a size which is above a third        size-threshold, and    -   the degree of slackening of the wire in an upper range, if the        wire has a length which is between the first and third        length-threshold and/or the objects have a size which is between        the first and third size-threshold,

wherein the first length-threshold is below the third length-thresholdand the first size-threshold is below the third size-threshold, and

wherein the wire is slackened less in the lower range than in the middlerange and more in the upper range than in the middle range.

In one embodiment, the degree of slackening of the wire is in the middlerange, if the wire has a length which is between the first and a secondlength-threshold and/or the objects have a size which is between thefirst and a second size-threshold and wherein

the first length-threshold is below the second length-threshold, and thesecond length-threshold is below the third length-threshold, and

the first size-threshold is below the second size-threshold, and thesecond size-threshold is below the third size-threshold.

Again, as is the case for the binding apparatus according to the firstaspect, the wire—in the method—be slackened on the basis of a polynomialin which at least one indeterminate is the length of the tightened wireor the size of the objects. The polynomial may be a fourth, a fifth, asixth, a seventh etc. degree polynomial.

Once de desired degree of slackening has been achieved, the wire may bebound. Accordingly, the method may comprise the step of: binding thewire when the desired degree of slackening has been achieved.

In one, embodiment the torque needed to bind the wire is constantlymonitored during the binding process and once a predetermined torque isneeded to continue the binding process, the process may be terminated.This may be done as it will be assumed that the desired tension in thebinding has been reached, when the torque has reached the predeterminedpoint.

Moreover, the wire may be bound by means of binding apparatus defining awire path for guiding a wire around one or more objects, the bindingapparatus comprising:

-   -   a wire supply for advancing the wire into the wire path; and    -   a binding tool adapted to guide the wire into and out of the        wire path, the binding apparatus comprising a retainer for        retaining a front end of the wire and being rotatable relative        to the wire path; and    -   wherein the step of placing the wire comprises the step of        advancing the front end of the wire into the wire path such that        the wire is guided around the objects and the front end is        received in the binding tool and is retained therein by the        retainer.

In one embodiment, the step of binding the wire comprises the step of:

-   -   adjusting the distance from spacing elements of the binding        apparatus; and    -   tightening the wire such that a predetermined tension in the        wire is achieved.

The invention according to the second aspect may comprise anycombination of features and elements of the invention according to thefirst and/or third and/or fourth and/or fifth aspect of the invention.

In a THIRD aspect, the present invention relates to the use of apolynomial to determine the degree of slackening of a wire in a bindingapparatus so as to achieve a desired/predetermined degree of tightnessof the bound wire. The binding apparatus may be a binding apparatusaccording to the first aspect of the invention.

The invention according to the third aspect may comprise any combinationof features and elements of the invention according to the first and/orsecond and/or fourth and/or fifth aspect of the invention.

In a FOURTH aspect, the present invention relates to a jaw for a bindingtool, the jaw comprising a shaping tool for shaping a wire to have apredetermined curvature, the shaping tool comprising at least threeshape-defining surfaces which are arranged with respect to each other,such that a wire which is moved translationally into the shaping tool isreshaped so as to define a predetermined curvature.

The jaw tool according to the second aspect of the invention maycomprise any feature or element according to the first aspect of theinvention. As an example, the shaping tool may be shaped such that upontightening of a wire received in the tool, the wire is brought out ofengagement with the shaping tool.

The fourth aspect of the invention may comprise one or more of thefollowing embodiments:

Embodiment Nineteen

A jaw for a binding tool, the jaw comprising a shaping tool for shapinga wire to have a predetermined curvature, the shaping tool comprising atleast three shape-defining surfaces which are arranged with respect toeach other, such that a wire which is moved translationally into theshaping tool is reshaped so as to define a predetermined curvature.

Embodiment Twenty

A jaw according to embodiment nineteen, wherein the shaping tool isshaped such that upon tightening of the wire, the wire is brought out ofengagement with the shaping tool.

The invention according to the fourth aspect of the invention maycomprise any combination of features and elements of the first and/orsecond and/or third and/or fifth aspect of the invention.

The invention according to the fourth aspect may comprise anycombination of features and elements of the invention according to thefirst and/or second and/or third and/or fifth aspect of the invention.

In a FIFTH aspect the present invention relates to a binding apparatusdefining a wire path for guiding a wire around one or more objects, thebinding apparatus comprising:

-   -   a wire supply for advancing the wire into the wire path; and    -   a binding tool forming a passage for the wire into and out of        the wire path and being rotatable relative to the wire path,

wherein the wire supply comprises a sensor for determining a length ofat least a part of the wire.

The binding apparatus may be adapted to prevent a binding action if thewire of the wire supply is shorter than a predetermined length, such asa minimum wire-length required for a binding action. In one embodiment,the apparatus is adapted to signal to a user that the wire of the wiresupply does not have the specified length to perform a binding action.The signal may be an audio signal and/or a visual signal and/or atactile signal.

The fifth aspect of the invention may comprise the one or more of thefollowing embodiments:

Embodiment Twenty One

A binding apparatus defining a wire path for guiding a wire around oneor more objects, the binding apparatus comprising:

-   -   a wire supply for advancing the wire into the wire path; and    -   a binding tool forming a passage for the wire into and out of        the wire path and being rotatable relative to the wire path,

wherein the wire supply comprises a sensor for determining a length ofat least a part of the wire.

Embodiment Twenty Two

A binding apparatus according to embodiment twenty one, wherein thebinding apparatus is adapted to prevent a binding action if the wire ofthe wire supply is shorter than a predetermined length.

Embodiment Twenty Three

A binding apparatus according to embodiment twenty two, wherein thepredetermined length is a minimum wire-length required for a bindingaction.

The invention according to the firth aspect may comprise any combinationof features and elements of the invention according to the first and/orsecond and/or third and/or fourth of the invention.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be described in further detail with reference tothe drawings in which:

FIG. 1 discloses a binding apparatus according to the present invention,

FIGS. 2 a-2 d disclose a resilient space defining element,

FIGS. 3 a-3 d illustrate the effect of a resilient space definingelement,

FIG. 4 discloses a binding apparatus prior to operation,

FIGS. 5-8 disclose the process of feeding the wire into and aroundobjects to be bound,

FIGS. 9-11 disclose the process of binding the wire,

FIG. 12 discloses removal of the binding apparatus,

FIG. 13 discloses a wire supply according to the invention,

FIGS. 14 a-14 d disclose a binding apparatus comprising spacers, and

FIG. 15 discloses a graph illustrating the degree of slackening of thewire as a function of the length of the wire and/or the size of theobjects to be bound.

DETAILED DESCRIPTION OF THE FIGURES

FIG. 1 discloses a binding apparatus 100 according to the presentinvention. The binding apparatus comprises a handle 206, an activationbutton 208 and a battery pack 210. During use, a user operates theapparatus 100 by holding the handle 206 in the hand such that the indexfinger is able to press the activation button 208. When the activationbutton 208 is pressed towards the handle 206, the apparatus 100initiates the binding process. The wire (not shown) is provided in therear part of the apparatus 100 such that it is protected by the wirecover 212. The binding apparatus 100 comprises a binding tool 104 whichis described in further detail in relation to FIG. 4-10.

The binding tool comprises a one or more space defining elements 170. Inthe embodiments of FIGS. 2 a-2 d and 14 a-14 d, the binding apparatus100 comprises two space defining elements 170, however it will beappreciated that any number of space defining elements 170 may beprovided. The space defining elements 170 are adapted to space theobjects 130 apart from the binding tool 104. The objects 130 and thebinding tool 104 are illustrated in FIGS. 4-10. The space definingelements 170 are adapted to vary the distance from the objects 130 tothe binding tool 104 in response to the torque transferred from thebinding tool 104 to the wire 118 during binding and/or the axial tensionin the wire 118 during binding and/or the axial pressure exerted on thespace defining elements 170 during binding.

In the embodiment of FIGS. 2 a-2 d, resilient elements 214 in the formof springs are arranged to bias the space defining elements 170 towardsa distal position. In all of the FIGS. 2 a-2 d, the space definingelements 170 are illustrated in their distal position. In FIGS. 2 a-2 d,the space defining elements are pivotally arranged by means of hinges216. Due to the pivotal arrangement, the space defining elements 170 aremoveable between a distal position in which the space defining elements170 abut a distal protrusion 218 and a proximal position in which thespace defining element 170 abuts a proximal protrusion 220. Due to theprovision of the resilient element 214, the space defining element isbiased towards the distal position. It will be appreciated that thelarger the force acting on the space defining elements 170 duringbinding is, the more the space defining elements are forces away fromthe distal position and towards the proximal position i.e. in thedirection of the binding apparatus—see FIG. 1. It will also beappreciated that the larger the spring constant of the resilient elementis the larger must be the force which is needed to bias the spacedefining element away from the distal position.

The binding process is illustrated in FIGS. 3 a-3 d, FIGS. 3 a and 3 billustrate the point in time in binding process in which the wire piece156 has been guided around the reinforcing bars 130 and is ready to betwisted, thus these Figs. correspond to FIG. 9 in the below descriptionof the binding process. FIGS. 3 c and 3 d illustrate the point in timein the binding process in which the wire ends have been twisted aroundeach other. Thus the latter two figures correspond to FIG. 10 in thebelow description of the binding process. Moreover, FIGS. 3 a and 3 cillustrate a situation in which the reinforcing bars are relatively thine.g. 6 mm thick, whereas FIGS. 3 b and 3 d illustrate a situation inwhich the reinforcing bars are relatively thick e.g. 20 mm thick.

Initially (FIGS. 3 a and 3 b), the space defining element 170 isprovided in its distal position in which the distance from the bindingtool 104 to the nearest reinforcing bar 130 is ‘A’. In this situationthe wire ends must be bent around the circumference of the reinforcingbars in order for them to meet during binding. This is illustrated byarrows 222 and 224. It will be appreciated that the circumferentialdistance —indicated by arrow 224—is longer on the thick bar in FIG. 3 bthan in the circumferential distance—indicated by arrow 222—of thin bar130 in FIG. 3 a. Accordingly when the wire has been bent around thecircumference, the remaining part of the wire which can be used fortwisting the wire ends, may not be sufficiently long to allow the wireends to be twisted the predetermined number of times, i.e. two times inthe embodiment of FIGS. 3 c and 3 d. This is especially the case withthicker bars where the circumferential distance is longer.

As the binding apparatus 100 is programmed to twist the wire apredetermined number of times, the axial tension in the wire piece 156is larger when the reinforcing bars 130 are thick (FIG. 3 b) than whenthe reinforcing bars 130 are thin. The effect is that the resilientspace defining elements 170 is compressed more during binding when thereinforcing bars are thick than when they are thin. This compressionallows for a larger part of the wire to be twisted whereby thepredetermined number of twists may be achieved. The result is that thebinding tool 104 is moved closer to the reinforcing bars 130 duringbinding of wider bars relative to binding of thinner bars. This isillustrated by the distances ‘A1’ and ‘A2’ in FIGS. 3 c and 3 d. InFIGS. 3 c and 3 d the space defining elements are not illustrated forsimplicity reasons.

From the above it will be appreciated that the provision of resilientspace defining elements provides a solution to the problem of ensuringthat the wire piece 156 has the desired tension—i.e. not too loose andnot so tight that the wire piece breaks, when it has been twisted apredetermined number of times.

FIGS. 4-12 disclose a binding apparatus 100 defining a wire path andcomprising a wire supply 160 (cf. FIG. 13), a rotatable spindle 102, anda binding tool 104. The binding tool 104 comprises a binding head 106and an inner tool member 108 which is slidingly received in the bindinghead 106 such that the inner tool member 108 and binding head 106 arelocked for relative rotation of one relative to the other.

The inner surface (not shown) of the inner tool member 108 is threadedand engages a threaded outer surface 110 of the spindle 102, such thatrotation of the spindle 102 causes the inner tool member 108 to moveaxially (to the right in the drawing) relative to the binding head 106and towards a locking position (shown in FIG. 10) in which the innertool member 108 is locked for axial movement relative to the bindinghead 106 whereby further rotation of the spindle 102 causes concurrentrotation of the inner tool member 108 and the binding head 106.

The binding apparatus 100 further comprises a cutting tool 112comprising a first cutting edge 114 and a contact surface 116. The firstcutting edge 114 and the contact surface 116 are arranged to perform acutting action when the first cutting edge 114 slides past the contactsurface 116. During said cutting action, the first cutting edge 114 isforced in the direction indicated by arrow 117, such that a wire 118feed into a first passage 120 is forced into contact with the contactsurface 116 which prevents the wire 118 from moving in the direction ofarrow 117, whereby further movement of the first cutting edge 114courses the wire 118 to be cut.

The wire supply 160 (cf. FIG. 13) is arranged to supply the wire 118through the first passage 120 and back into a second passage 122 via afirst guiding jaw 124 and a second guiding jaw 126. At least a part ofthe wire path is defined by the first and second guiding jaws (124,126).The first and second guiding jaws 124,126 together define a cavity 128wherein one or more objects 130, such as reinforcing bars, may bepositioned so as the bind the one or more objects 130 together by meansof the binding apparatus 100. In order to allow the objects to bepositioned in the cavity 128, a part of the wire path is “broken”, suchthat when the wire 118 is not feed from the first to the second guidingjaw 124,126, the objects 130 may be moved into the cavity 128, and suchthat when the wire 118 is feed from the first guiding jaw 124 to thesecond guiding jaw 126, the objects 130 cannot be moved into or out ofthe cavity 128 as the wire 118 prevents such movement.

Moreover, the first guiding jaw 124 comprises a shaping tool 132 adaptedto shape/bend the wire 118 when feed through a passage 134 of shapingtool 132. The shaping tool 132 is adapted to shape/bend the wire 118 tohave a curvature allowing the wire 118 when feed from the first guidingjaw 124 to be received by the second guiding jaw 126 and further intothe second passage 122.

In FIG. 4 discloses an initial position wherein the first and secondguiding jaws 124,126 are positioned around the objects 130 such that theobjects are positioned in the cavity 128. The inner tool member 108 ispositioned in an initial position, wherein it is retracted relative tothe binding head 106 (i.e. positioned to the left in the drawing). Thewire 118 abuts the second cutting edge 116 and is ready for insertioninto the first passage 120, cf. FIG. 4.

In FIG. 5 the spindle 102 is rotated in a first rotational directionwhereby the threaded engagement between the outer surface of the spindle102 and the inner surface of the inner tool member 108 causes the innertool member 108 to be moved axially (i.e. to the right in the drawing)relative to the binding head 106 and in the direction of (but not into)a locking position (cf. FIG. 10). In order to prevent the binding head106 from rotating with the spindle 102, the binding head 106 ispartially locked for rotation relative to the wire path. The partiallock is adapted to prevent said relative rotation, as along as a torqueapplied to the binding head is below a predetermined threshold and has adirection opposite the first rotational direction. Accordingly, if thetorque is above the predetermined threshold and in the direction of thefirst rotational direction, the binding head 106 may be rotated.Accordingly, the inner tool member is in its locking position, rotationof the spindle 102 cannot be transformed into translational movement ofthe inner tool member, whereby the torque needed to rotate the spindle102 must exceed said predetermined threshold in order to allow thespindle to be rotated further. This is described in further detail inrelation to FIG. 10.

In FIGS. 6-8 the wire supply 160, which is described in relation to FIG.13, advances the wire 118 into the first passage 120 wherein a guidingsurface 136 guides the wire 118 into the passage 134 of the shaping tool132 which shapes/bends the wire 118 to have a curvature corresponding tothe curvature of the first and second guiding jaws 124,126.Subsequently, the wire 118 follows a first guiding surface 138 of thefirst guiding jaw 124. Due to the reshaping of the wire 118 provided bythe shaping tool 132, the wire 118 is received by the second guiding jaw126, and slides along a second guiding surface 140 of second guiding jaw126 until the wire 118 is received in the second passage 122. Uponfurther feeding of the wire 118, the wire end 142 is moved intoengagement with a retainer in the form of a pawl 144 which locks thewire for movement in the reverse direction as indicated by arrow 146.The pawl 144 is pivotable about a retainer axis 148 and a spring (notshown) urges the pawl 144 towards the sidewall 150. The wire end 142 isretained between the pawl 144 and the sidewall 150 and reverse movementof the wire (in the direction of the arrow 146) urges the retainertowards the wire and the sidewall. The wire 118 is prevented fromfurther advancement into the second passage 122 when a feed/fed end 154abut a stopping surface 151, and the wire supply 160 halts the feedingprocess, as is described in relation to FIG. 13.

In FIG. 9 the wire supply 160 pulls the wire 118 in the reversedirection, as indicated by arrow 146. This tightens the wire 118,whereby the wire 118 is pulled out of the passage 134 of the shapingtool 132 and is tightened around a part of the objects 130. In order toachieve this, the shaping tool 132 may be open in one side, i.e. in adirection into or out of FIG. 9. Moreover, a downstream surface 133 ofthe shaping tool may be designed to force the wire 118 towards the openside upon tightening of the wire 118. With the wire 118 tightened aroundthe reinforcing bars 130, the spindle 102 is rotated whereby the innertool member 108 is moved into its locking position as illustrated inFIG. 10. During said movement the wire 118 is cut by the first cuttingedge 114 and the contact surface 116, whereby a wire piece 156 isproduced, said wire piece 156 has a feed/fed end 154 and a cut end 155.When the inner tool member 108 is positioned in the locking position,the wire 118 is retained between the inner tool member 108 and theabutment surface 152. With the inner tool member 108 in its lockingposition, further rotation of the spindle 102 causes the inner toolmember 108 and binding head 106 to rotate, when the torque applied tothe spindle exceeds the predetermined threshold. Upon said rotation, thewire is twisted as the feed/fed end 154 and the cut end 155 are retainedin the binding tool 104.

With the objects 130 bound to each other, the spindle 102 is rotated inthe opposite direction as illustrated in FIG. 11. As the binding head106 is prevented from rotating in the opposite direction, rotation ofthe spindle in said direction causes the inner tool member 108 to bemoved away from its locking position, whereby the ends 154,155 of thewire piece 156 are straightened out due to the elements 158,159.Subsequently the binding apparatus 100 may be removed as shown in FIG.12.

An embodiment of the wire supply 160 is illustrated in FIG. 13. The wiresupply 160 comprises a wire coil 162, a first sensor 164, feedingrollers 166 and a second sensor 168. When the wire supply 160 is empty,the wire 118 may be feed into the wire supply 160, so as to allow thewire 118 to be received by the feeding rollers 166. Prior to receipt ofthe wire 118 by the rollers 166, the first sensor 164 detects thepresence of a wire 118, whereby a motor (not shown) causes the rollersto rotate. When the wire 118 is received by the rollers 166, the rollersare rotated until the wire 118 is detected by the second sensor 168 andthe further advancement of the wire is halted, when the free end is inthe correct feeding position.

Upon initiation of a user of the binding apparatus, the motor isoperated whereby the rollers rotate and the wire 118 is feed via thewire path into the second passage 122 as described above. When the wireend abuts the stopping surface 151 of the second passage the wire isprevented from being advanced further and the current in the electricalcircuit connected to the motor increases. Accordingly, when the controlsystem controlling the motor detects such an increase in the current,the rotational direction of the motor (rollers) are reversed in order totighten the wire as described in relation to FIG. 9. In an alternativeembodiment, the number or revolutions of the rollers are used todetermine whether the wire has been advanced sufficiently to be receivedin the second passage 122.

The binding apparatus comprises a revolution counter adapted to countthe number of revolutions made by the feeding rollers 166. As onerevolution of the feeding rollers 166 corresponds to a predeterminedlength of wire 118, the revolution counter is adapted to output a signalcorresponding to a wire length.

The apparatus 100 is adapted to be operated as follows: If duringfeeding of wire 118 the first sensor 164 is no longer able to detect thewire 118 i.e. the wire supply is empty, the apparatus is, by means ofthe revolution counter, be adapted to determine the length of the wire118 which, in connection with the current binding action, has alreadybeen feed by means of the rollers 166. If said length is below apredetermined length e.g. the length needed to perform a binding action,the binding apparatus is adapted to retract the feed wire 118 and signalto the user, that the wire 118 is not long enough for binding and that anew wire should be inserted into the wire supply.

FIGS. 14 a-14 d disclose a binding apparatus 100 comprising two spacers170, which during binding are used to provide a predetermined distancebetween the objects and the binding head. By providing a predetermineddistance the tightness of the bindings may be controlled, as it will beappreciated that the longer the distance is the more loose the bindingis, and the shorter the distance is the tighter the binding is, for thesame size of objects 130. Accordingly, a user may advance the bindingapparatus into a position wherein one or more of the objects 130 abutthe spacers 170, whereby the predetermined distance between the bindingtool 104 and the objects 130 is ensured.

In a first embodiment the axial extent of the spacers is adjustable. Theadjustability may be ensured by providing a plurality of interchangeablesets of spacers each having different lengths. Alternatively, thespacers may be adapted to be moved axially between two positions betweenwhich the spacers may be positioned in order to achieve the desiredtightness of the bindings. The user may adjust the adjustable spacersmanually or automatically by means of a motor.

In a second embodiment the spacers are provided in a predeterminedlength and the tightness of the binding is controlled by adjusting thetightening of the wire either manually or automatically. In order tocontrol the tightening of the wire the apparatus may be adapted totighten the wire as much as possible and subsequently loosen the wire inorder to achieve the desired tightness. The apparatus may be adapted toallow the user to adjust the tightening/loosening of the wire manuallyor automatically. The latter may be achieved by the following stepswhich the apparatus may be adapted to carry out:

In a first step, a predetermined length of wire is advanced out thoughthe binding head. When the wire end is received by the wire head afterhaving been guided around the objects 130, the wire end is retained andthe wire is tightened by retracing the wire as much as possible.

In a second step, the length of the retracted part of the wire isdetermined (i.e. it is determined how much wire can be retracted untilthe wire is as tight as possible). It will be appreciated that thelonger the retracted wire is the smaller the objects are, and theshorter the retracted wire is the larger the objects are. Thus, theapparatus may be adapted to determine how much the wire need to beloosened in order to ensure a desired tightness of the binding for anysize of the object(s).

In a third step the wire is loosened in order to ensure the desiredtightness of the binding.

FIG. 15 illustrates a graphical representation 172 of the slackening ofthe wire. The first axis 174 is a representation of the length of thewire 118 and/or the size of the object 130 and the second axis 176 is arepresentation of the degree of slackening. Thus, the graph 178represents the degree of slackening of the wire as a function of thelength of the wire 118 and/or the size of the objects 130.

FIG. 15 illustrates two embodiments (which may be combined). In thefirst embodiment, the degree of slackening of the wire 118 is thelowest, when the wire 118 has a first length and/or the objects 130 havea first size—this is illustrated by the point 180. In some cases, theapparatus specifies a minimum length of the wire which is illustrated bypoint 180′. In such cases, the apparatus cannot perform a binding inwhich the wire length is below said minimum length.

Moreover the first embodiment, the degree of slackening of the wire 118,is the highest, when the wire 118 has a second length and/or the objects130 have a second size. This is illustrated by point 182.

In the first embodiment, the degree of slackening of the wire 118 isbetween said lowest and highest slackening (point 180/180′ and 182,respectively), if the wire 118 has a third length and/or the objects(130) have a third size.

It will be appreciated from FIG. 15 that the third length/size may berepresented on the graph 178 as any position on the graph 178 which isdifferent from the points 180/180′ and 182. Accordingly, the point maybe a point between the points 180/180′ and 182 or a point to the rightof the point 182. In a second embodiment of FIG. 15, a lower range 184,a middle range 186 and an upper range 188 are defined.

The wire is slackened such that the degree of the slackening of the wire118 is in the lower range 184, if the wire 118 has a length which isbelow a first length-threshold 190 and/or the objects (130) have a sizewhich is below a first size-threshold 190. This is illustrated by alower hatched-area 192.

Moreover, the degree of slackening of the wire 118 is in the middlerange 186, if the wire 118 has a length which is between the firstlength-threshold 190 and a second length-threshold 194 and/or theobjects have a size which is between the first size-threshold 190 and asecond size-threshold 194. This is illustrated by firstmiddle-hatched-area 196.

Additionally, the degree of slackening of the wire 118 in the upperrange 188, if the wire 118 has a length which is between the secondlength-threshold 194 and a third length-threshold 198 and/or the objectshave a size which is between the second size-threshold 194 and thirdsize-threshold 198. This is illustrated by an upper-hatched-area 200.

Finally, the degree of slackening of the wire 118 is in the middle range186, if the wire 118 has a length which is above the thirdlength-threshold 198 and/or the objects have a size which is above thethird size-threshold 198. This is illustrated by a second middle hatchedarea 202.

The invention claimed is:
 1. A method of binding a wire around one ormore objects so as to achieve a predetermined tension of the wire in thebinding, the method comprising the steps of: advancing a front end ofthe wire into a wire path thereby guiding and placing a length of thewire around the objects such that two parts of the wire extend in thesame direction, determining the length of the advanced wire, binding thewire such that a predetermined tension in the wire is achieved, whereinthe step of binding the wire comprises the step of: tightening the wireby retracting the wire; determining the length of the retracted wire andthereby the length of the tightened wire, and slackening the wire alength in dependence on the length of the tightened wire such that: thewire is slackened a predetermined length A, if the length of thetightened wire is below a first length-threshold T1, the wire isslackened a predetermined length B, if the length of the tightened wireis above a second length-threshold T2 and below a third length-thresholdT3, the second and third length-thresholds being greater than the firstlength-threshold T1, and the wire is slackened a predetermined length C,if the length of the tightened wire is above the third length-thresholdT3, wherein the length C is larger than the length A but smaller thanthe length B.
 2. The method according to claim 1, wherein the wire isslackened the predetermined length C, if the length of the tightenedwire is between the first T1 and the second length-threshold T2.
 3. Themethod according to claim 1, wherein the length A, B, or C aredetermined as a polynomial function of at least the length of thetightened wire.
 4. The method according to claim 3, wherein thepolynomial function is at least a fourth degree polynomial.
 5. Themethod according to claim 1, further comprising the step of: binding thewire upon the step of slackening the wire.
 6. The method according toclaim 1, wherein the wire is bound by means of a binding apparatusdefining the wire path for guiding the wire around the one or moreobjects, the binding apparatus comprising: a wire supply for advancingthe wire into the wire path; and a binding tool configured to guide thewire into and out of the wire path, the binding apparatus furthercomprising a retainer for retaining a front end of the wire and beingrotatable relative to the wire path; and wherein the step of placing thewire around the objects comprises the step of advancing the front end ofthe wire into the wire path such that the wire is guided around theobjects and the front end is received in the binding tool and isretained therein by the retainer.
 7. The method according to claim 6,wherein the binding apparatus comprises one or more space definingelements configured to space the objects apart from the binding tool,and wherein the step of binding the wire further comprises the step ofmoving the space defining elements of the binding apparatus such as toadjust the distance between the binding tool and the objects.